A future release will change the default boot mode from legacy BIOS
to UEFI. The default boot mode can be set to
[deploy]/default_boot_mode option for hardware types which support
setting boot mode. Otherwise, the default boot mode is hard-coded as
legacy BIOS.
This patch recommends to set boot mode explicitly in a help message of
[deploy]/default_boot_mode option. A warning message is also logged
when a default hard-coded boot mode is used. This message is logged
once even if there are multiple nodes whose boot modes are configured
explicitly for not emitting too many messages.
Change-Id: Ib90ebf59ba72d49cb757e44f3741b5373a411ddf
Story: 2003936
Task: 27475
60767aee61